To investigate the protective effect of L-carnitine on myocardial ischemia-reperfusion injury in rat heart,all harvested isolated hearts were perfused on Langendorff apparatus with oxygenized K-H solution for 20 min. ...To investigate the protective effect of L-carnitine on myocardial ischemia-reperfusion injury in rat heart,all harvested isolated hearts were perfused on Langendorff apparatus with oxygenized K-H solution for 20 min. The hearts were then exposed to ischemia for 30 min. Following the ischemia the hearts were re-perfused with K-H solution for 120 min to serve as the control group A. Either 5 or 10 mmol/L of L-carnitine was added into the K-H solution for 20 min at the beginning of reperfusion to generate group B and group C, respectively. The derivatives of the intraventricular pressure curve (DP/DT), left ventricular developed pressure (LVDP), and coronary flux were monitored during the entire experiment. The levels of ATP, hepatin, malondialdehyde (MDA), and superoxide dismutase (SOD) in tissue, and lactic dehydrogenase (LDH), creatine phosphate kinase (CPK), malondialdehyde (MDA), and superoxide dismutase (SOD) concentration in the coronary efflux were all measured. Compared with the control group, the treatment with L-carnitine resulted in better results, i. e. , higher DP/DTmax and LVDP. At the same time, ventricular fibrillation was reduced, and the levels of ATP, hepatin and SOD were all elevated. However, the concentrations of MDA, CPK and LDH were all reduced. In conclusion, L-carnitine has a protective effect on ischemia-reperfusion injury, which is partly due to its prevention of energy loss and its antioxidant activity.展开更多
L-carnitine selective polymers were prepared by molecular imprinting using methacrylic acid as the functional monomer. The acid function of the monomer is expected to form hydrogen bond and ionic interactions with th...L-carnitine selective polymers were prepared by molecular imprinting using methacrylic acid as the functional monomer. The acid function of the monomer is expected to form hydrogen bond and ionic interactions with the amine function of the target molecule L-carnitine. The imprinted polymers were used as stationary phases in high-performance liquid chromatography (HPLC). It was shown that L-carnitine imprinted polymer exhibited a higher affinity to its template molecule, while the non-imprinted polymer had no affinity to the compounds tested. Racemic carnitine hydrochloride was efficiently resolved on the L-carnitine imprinted polymer, and the separation factor is 1.9.展开更多
A simple and rapid UPLC–MS/MS method to simultaneously determine gemcitabine and its L-carnitine ester derivative(2’-deoxy-2’, 2’-difluoro-N-((4-amino-4-oxobutanoyl) oxy)-4-(trimethyl amm-onio) butanoate-cytidine,...A simple and rapid UPLC–MS/MS method to simultaneously determine gemcitabine and its L-carnitine ester derivative(2’-deoxy-2’, 2’-difluoro-N-((4-amino-4-oxobutanoyl) oxy)-4-(trimethyl amm-onio) butanoate-cytidine, JDR) in rat plasma was developed and validated.The conventional plasma sample preparation method of nucleoside analogues is solidphase extraction(SPE) which is time-consuming and cost-expensive. In this study, gradient elution with small particles size solid phase was applied to effectively separate gemcitabine and JDR, and protein precipitation pretreatment was adopted to remove plasma protein and extract the analytes with high recovery(>81%). Method validation was performed as per the FDA guidelines, and the standard curves were found to be linear in the range of 5–4000 ng/ml for JDR and 4–4000 ng/ml for gemcitabine, respectively. The lower limit of quantitation(LLOQ)of gemcitabine and JDR was 4 and 5 ng/ml, respectively. The intra-day and inter-day precision and accuracy results were within the acceptable limits. Finally, the developed method was successfully applied to investigate the pharmacokinetic studies of JDR and gemcitabine after oral administration to rats.展开更多
A variety of natural and artificial cryoprotectant extenders have been explored to enhance sperm recovery following cryopreservation-thawing process. The current investigation is aimed at evaluating the effect of acet...A variety of natural and artificial cryoprotectant extenders have been explored to enhance sperm recovery following cryopreservation-thawing process. The current investigation is aimed at evaluating the effect of acetyl-L-carnitine on human spermatozoa and reactive species oxygen(ROS) level after freezing-thawing process. The spermatozoa were collected from 35 male patients diagnosed as having asthenospermia. The cryopreservation of human spermatozoa treated with acetyl-L-carnitine at different concentrations(group B: 2.5 mmol/L, group C: 7.5 mmol/L, group D: 15 mmol/L) was compared with control(group A: no acetyl-L-carnitine given). For the frozen-thawed spermatozoa, the viability, motility and DNA integrity were measured by comet assay, acrosome integrity by FITC-PNA staining and ROS level was determined in each group. The results showed that there were no significant differences in motility and viability between group A and group B, while the motility and viability of spermatozoa in group C and group D were significantly increased as compared with those in group A. As compared with group A, the values for DNA integrity parameters including comet rate(CR), tail DNA percentage(TD), tail length(TL) and Oliver tail moment(OTM) were significantly reduced in group C and group D. Group C and group D also displayed a higher proportion of intact acrosome than group A. No significant difference in ROS level was found between group A and group B, while with the increase in acetyl-L-carnitine concentration, the ROS level in groups C and D was significantly reduced as compared with that in group A. In conclusion, acetyl-L-carnitine at a concentration of 7.5 mmol/L is an effective antioxidant against cryo-damage on post-thawed human spermatozoa.展开更多
Several studies have demonstrated that L-carnitine exhibits neuroprotective effects on injured sciatic nerve of rats with diabetes mellitus. It is hypothesized that L-carnitine exhibits neuro-protective effects on inj...Several studies have demonstrated that L-carnitine exhibits neuroprotective effects on injured sciatic nerve of rats with diabetes mellitus. It is hypothesized that L-carnitine exhibits neuro-protective effects on injured sciatic nerve of rats. Rat sciatic nerve was crush injured by a forceps and exhibited degenerative changes. After intragastric administration of 50 and 100 mg/kg L-carnitine for 30 days, axon area, myelin sheath area, axon diameter, myelin sheath diameter, and numerical density of the myelinated axons of injured sciatic nerve were similar to normal, and the function of injured sciatic nerve also improved signiifcantly. These ifndings suggest that L-carnitine exhibits neuroprotective effects on sciatic nerve crush injury in rats.展开更多
Summary: The effects of L-carnitine, as an ingredient of cardioplegia solution, on cardiac function and cardiomyocyte apoptosis in patients undergoing heart valve replacement operation were investigated. Twenty-three...Summary: The effects of L-carnitine, as an ingredient of cardioplegia solution, on cardiac function and cardiomyocyte apoptosis in patients undergoing heart valve replacement operation were investigated. Twenty-three cases undergoing heart valve replacement with cardiopulmonary bypass (CPB) were randomly allocated into two groups: L-carnitine group (n=12, 12 g/L L-carnitine was put in the ST. Thomas cardioplegia) and control group (n=11, identical to the L-carnitine group except that normal saline was administered instead of L-carnitine). Serum cardial troponin I (cTnI) levels, the left ventricular ejection fraction (LVEF), and cardiac index (CI) were measured perioperatively. A bit of myocardial tissue obtained from right atria was taken before CPB and by the end of intracardiac procedure to undergo electron microscopy examination and estimate apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL). From the end of CPB to 3 days after operation, the serum levels of cTnI in the L-carnitine group was significantly lower than that in the control group (P〈0.05). Heart color ultrasonogram showed that the CI index and LVEF at 7th day postoperatively in the L-carnitine group were significantly higher than in the control group (P〈0.05). Compared to the control group, L-carnitine significantly alleviated the morphologic changes of cardiac muscle cells (electron microscopy examination) and decreased the amounts of apoptotic cardiac muscle cells (TUNEL). Furthermore, the dosage of vasoactive drugs used after operation was significantly less in the L-carnitine group (P〈0.01). It was concluded that L-carnitine cardioplegia solution could improve cardiac function in patients undergoing heart valve replacement operation and alleviate CPB-mediated apoptosis of cardiac muscle cells.展开更多
BACKGROUND Non-alcoholic fatty liver disease(NAFLD)dominates the landscape of modern hepatology.Affecting 25%of the general population,there is critical unmet need to identify broadly available,safe and cost-effective...BACKGROUND Non-alcoholic fatty liver disease(NAFLD)dominates the landscape of modern hepatology.Affecting 25%of the general population,there is critical unmet need to identify broadly available,safe and cost-effective treatments.Cumulative evidence in animal and human models suggests that intrahepatic and skeletal muscle fatty acid oxidation is impaired in NAFLD,such that lipid accretion is not matched by efficient utilisation.L-carnitine is a crucial mediator of fatty acid metabolism in vivo,promoting mitochondrial lipidβ-oxidation and enhancing tissue metabolic flexibility.These physiological properties have generated research interest in L-carnitine as a potentially effective adjunctive therapy in NAFLD.AIM To systematically review randomised trials reporting effects of dietary L-carnitine supplementation on liver biochemistry,liver fat and insulin sensitivity in NAFLD.METHODS Search strategies,eligibility criteria and analytic methods were specified a priori(PROSPERO reference:CRD42018107063).Ovid MEDLINE,Ovid EMBASE,PubMed,Web of Science and the Cochrane Library were searched from their inception until April 2019.Outcome measures included serum concentrations of alanine and aspartate aminotransferase(ALT and AST),liver fat and insulin sensitivity assessed by the homeostasis model of insulin resistance(HOMA-IR).A random effects meta-analysis was performed for,ALT,AST and HOMA-IR measures separately.Between-study heterogeneity was measured using I2 statistics.RESULTS Five eligible randomised trials were included in the qualitative and quantitative synthesis(n=338).All of the 5 included trials assessed the effect of L-carnitine on serum ALT,identified from Italy,South Korea and Iran.Weighted mean difference(WMD)for ALT between L-carnitine and control groups after intervention was-25.34 IU/L[95%CI:-41.74-(-8.94);P=0.002].WMD for AST between L-carnitine and control groups was-13.68 IU/L(95%CI:-28.26-0.89;P=0.066).In three studies(n=204),HOMA-IR was evaluated.WMD for HOMA-IR between L-carnitine and control groups was-0.74 units[95%CI:-1.02-(-0.46);P<0.001].Two studies using validated outcome measures reported a significant reduction in liver fat in L-carnitine vs control groups post-intervention(P<0.001).CONCLUSION Pooled results indicate that L-carnitine supplementation attenuates ALT,liver fat and insulin resistance in NAFLD cohorts,confirming a beneficial effect of Lcarnitine for a highly prevalent condition with a growing economic burden.展开更多
[ Objective] The paper was to study antioxidant effects of L-carnitine (LC) on rabbit, and explore its impact on SOD, GSH-PX, CAT, T-AOC and MDA activity in the plasma, brain tissue and cerebrospinal fluid of rabbit...[ Objective] The paper was to study antioxidant effects of L-carnitine (LC) on rabbit, and explore its impact on SOD, GSH-PX, CAT, T-AOC and MDA activity in the plasma, brain tissue and cerebrospinal fluid of rabbit. [ Method] The healthy matured New Zealand rabbits with big ears were intragastrically administrated with LC at the dose of lmL/kg, and SOD, GSH-PX, CAT, T-AOC and MDA activities in plasma, brain tissue and cerebrospinal fluid of rabbit were determined at different periods before and after administration, respectively. [Result] After LC administration, SOD, GSH-PX CAT, and T-AOC activity in plasma, brain tissue and cerebrospinal fluid increased significantly (P 〈 0.05 ), while MDA content decreased significantly (P 〈 0.05). [Condusion ] LC oral solution shows antioxidant effects on rabbit.展开更多
[Objective] To study the effects of L-carnitine (LC) on lowering the high blood lipid and antioxidation in hyperlipidemia rats. [Method] 50 healthy SD rats were randomly divided into 5 groups. They were fed with sta...[Objective] To study the effects of L-carnitine (LC) on lowering the high blood lipid and antioxidation in hyperlipidemia rats. [Method] 50 healthy SD rats were randomly divided into 5 groups. They were fed with standard diet, high-cholesterol diet and high-cholesterol diet with 0.25, 0.5, 1.0 g/( kg · d) LC. After the LC groups were consecutively orally administered LC for 28 days, rat serum total cholesterol ( TC), triglyceride (TG), high density lipoprotein ( HDL-C), low density lipoprotein (LDL-C) content, as well as super oxide dismutase (SOD) activity and malondial- dehyde (MDA) content in serum and liver were determined. [ Reset~ Compared with the high-fat model group, LC could significantly reduce the se- rum TC, TG, LDL-C levels, increase HDL-C level, and enhance SOD activity in serum and liver, decrease the content of MDA ( P 〈0.05). [ Con- Clusion] LC might have a significant role in lowering the high blood lipid and improving internal antioxidant capacity in hyperlipidemia rats.展开更多
The present study was aimed to observe the effects of urea ingestion, non-protein nitrogen, on the disorder of nitrogen metabolism with the L-carnitine contents using the blood, kidney, liver, and femoral muscle as ma...The present study was aimed to observe the effects of urea ingestion, non-protein nitrogen, on the disorder of nitrogen metabolism with the L-carnitine contents using the blood, kidney, liver, and femoral muscle as markers. A total of 8 Japanese white rabbits were used in this experiment. They were fed a basal diet prepared for the control group and the nitrogen volume proportionated to one-third of CP 14%, was replaced with urea in the feed of the experimental group for 7 days. On the final day, the animals were fasted from the previous evening and sacrificed. Blood was collected into a test tube at the same time of the sacrifice and their heart, kidney, liver and femoral muscle were collected. The L-carnitine contents in each sample and the urea in the blood were determined. The results of the growth test showed that there was no significant difference. Furthermore, there was no significant difference in the contents of L-carnitine and urea in each sample. It was concluded that nitrogen replacement of the diet with urea, in the range of 1/3 of dietary protein, had neither effect on the maintenance of body weight nor nitrogen balance, including the de novo synthesis of L-carnitine.展开更多
There is constant low level background radiation from the cosmos but in certain situation the body may be subjected to increased acute or chronic exposure from other sources. This occurs in situations such as radiatio...There is constant low level background radiation from the cosmos but in certain situation the body may be subjected to increased acute or chronic exposure from other sources. This occurs in situations such as radiation accidents, medical use and could possibly occur in military/terrorist incident. Dependent on the type, strength of the actual source, degree of exposure and type of radiation different strategies may be employed to reduce damage to the body tissues. A number of pharmacological agents such as peroxisome proliferator-activated receptor (PPAR) gamma agonists, diltiazem, amifostine and palifermin as well as antioxidants and metabolic compounds have been shown to be effective in preventing and also in reducing the long-term damage of the exposure of the living cells to radiation. The major drawback of synthetic (pharmacological) compounds has been that they are highly toxic at the optimum protective dose. Studies have shown that various endogenously found compounds such as L-carnitine, and its derivative acetyl-L-carnitine, are able to protect tissues and organs against various forms of toxic insult including radiation damage. The radiation-induced chronic injury may also be counteracted by other metabolic compounds with amine groups and antioxidant properties similar to the carnitines such as cysteine, 3,3’-diindolylmethane (DIM) and N-acetylcysteine. This review discuses the radioprotective compounds as well as the potential mechanism of cellular protection against radiation by carnitines and other compounds.展开更多
Background: Propofol inhibits fatty acid oxidation and induces mitochondrial deficiency, a possible mechanism involved in propofol infusion syndrome. This study investigated how propofol influences fatty acid, glucose...Background: Propofol inhibits fatty acid oxidation and induces mitochondrial deficiency, a possible mechanism involved in propofol infusion syndrome. This study investigated how propofol influences fatty acid, glucose, and amino acid metabolism, as well as whether L-carnitine may improve suppression of free fatty acid metabolism. Methods: Male Sprague-Dawley rats, fasted for 16 hours, were allocated to the following two groups: (Group P;continuous intravenous administration of 10 mg/kg/h propofol;n = 8) and (Group P + C;intravenous administration of 50 mg/kg and then 50 mg/kg/h L-carnitine continuously;n = 8). Concentrations of glucose, free fatty acid (FFA), amino acids, in-sulin, and β-hydroxybutyric acid were measured at the start and then one, two, and three hours after propofol administration. Intrahepatic triglyceride levels were measured at the end of experiments. In vitro experiments comprised measurement of oxygen consumption in human hepatocytes (Hepg2) and investigating dependency on palmitic acid, glucose, and glutamine as fuel during propofol administration, with or without L-carnitine. Results: FFA increased in Group P and gradually decreased in Group P + C. There were significant differences between the two groups (Group P;331.2 ± 64.5 μM vs. Group P + C;199 ± 73.6 μM). Glucose decreased in both groups (Group P;53.8 ±16.6 mg/dL vs. Group P + C;88 ± 11.3 mg/dL). Amino acid concentrations were higher in Group P + C after experiments;alanine and glutamine increased significantly. β-hydroxybutyric acid increased significantly in Group P + C, and intrahepatic triglyceride decreased in Group P + C. Dependency on fatty acid metabolism significantly decreased with propofol only;addition of L-carnitine prevented these effects. Conclusions: Propofol impaired mitochondrial fatty acid metabolism, which was compensated mainly by a switch to glucose metabolism and partially by amino acid metabolism. Addition of L-carnitine may improve this imbalance of energy metabolism.展开更多
One group of six male control rats [12 months old] and one group of six male rats of the same age, singularly maintained in a cage, and treated with acetyl-L-carnitine-HCl [(gamma-trimethyl-beta-acetyl-butyrobetaine-H...One group of six male control rats [12 months old] and one group of six male rats of the same age, singularly maintained in a cage, and treated with acetyl-L-carnitine-HCl [(gamma-trimethyl-beta-acetyl-butyrobetaine-HCl: Sigma-Tau code ST200 or ALCAR: 60 mg/kg/day[7]/po)] for six months were tested in the spatial learning/memory Morris mazewater task and for atrophy and cell loss in seven myelo- and cytostructurally defined basal forebrain (BF) cholinergic regions [Freddi et al., 2009]. Coronal sections 25 ?m thick were cut through the BF regions and processed every 200 ?m for choline acetyltransferase (ChAT) immunohistochemistry. The ALCAR-treated rats had significantly shorter exit times on the Morris maze-water task test than the control rats (average ± SD 28.3 ± 12.4 s vs. 61.16 ± 4.67 s;t = 6.07, DOF = 10, P = 0.0001). Degenerative morphological changes in the BF ChAT-positive cells were observed in the substantia innominata pars anterior of the control rats but not in the treated animals (P < 0.05). In the BF, the counted and estimated average number of ChAT + cells in the 12-month-old ALCAR-treated rats (ChAT-ALCAR-12+ [Nos. 2,3,4]) was higher but not significantly (15.288 ± 3281) than that counted and estimated in the 12-month-old control rats [(ChAT-CT-12 [Nos. 1,2,3]) (11.508 ± 3868), t = 1.82, DOF = 10, P = 0.319]. In the substantia innominata pars posterior, the ChAT+ cells were significantly more numerous (P < 0.05) in the 12-month-old ALCAR-treated rats (ChAT-ALCAR-12 + [Nos. 2,3,4]) than in the control rats (ChAT-CT-12 [Nos. 1,2,3]). Above all, these results dem-onstrate that treatment with ALCAR from the age of 6 up to 12 months significantly attenuated spatial learning/memory impairment on the Morris maze-water behavioral task (P < 0.001) and also importantly reduced degeneration in size and number of cholinergic cells in the nucleus basalis magnocellularis of the BF. Accordingly, the surviving cholinergic neurons found in the BF of the ALCAR-treated rats might play an important role in modulating cortical activity and facilitating processes of attention, learning and memory.展开更多
This study evaluated the relationship between serum L-carnitine level and sperm parameters in young boars. Serum L-carnitine and semen characteristics were determined for 61 young Duroc boars between the ages of 590 a...This study evaluated the relationship between serum L-carnitine level and sperm parameters in young boars. Serum L-carnitine and semen characteristics were determined for 61 young Duroc boars between the ages of 590 and 630 days. Multiple linear regression analysis was performed to predict total and progressive motility and the total number of spermatozoa based on serum total L-carnitine and free L-carnitine levels. Total number of spermatozoa was not associated with basal serum L-carnitine levels. A regression equation was found in which both total L-carnitine levels and free L-carnitine levels were significant predictors of total and progressive motility (P 0.05). These results suggest that serum L-carnitine level is an important selection parameter for stock boars.展开更多
文摘To investigate the protective effect of L-carnitine on myocardial ischemia-reperfusion injury in rat heart,all harvested isolated hearts were perfused on Langendorff apparatus with oxygenized K-H solution for 20 min. The hearts were then exposed to ischemia for 30 min. Following the ischemia the hearts were re-perfused with K-H solution for 120 min to serve as the control group A. Either 5 or 10 mmol/L of L-carnitine was added into the K-H solution for 20 min at the beginning of reperfusion to generate group B and group C, respectively. The derivatives of the intraventricular pressure curve (DP/DT), left ventricular developed pressure (LVDP), and coronary flux were monitored during the entire experiment. The levels of ATP, hepatin, malondialdehyde (MDA), and superoxide dismutase (SOD) in tissue, and lactic dehydrogenase (LDH), creatine phosphate kinase (CPK), malondialdehyde (MDA), and superoxide dismutase (SOD) concentration in the coronary efflux were all measured. Compared with the control group, the treatment with L-carnitine resulted in better results, i. e. , higher DP/DTmax and LVDP. At the same time, ventricular fibrillation was reduced, and the levels of ATP, hepatin and SOD were all elevated. However, the concentrations of MDA, CPK and LDH were all reduced. In conclusion, L-carnitine has a protective effect on ischemia-reperfusion injury, which is partly due to its prevention of energy loss and its antioxidant activity.
基金Research supported by The Analysis & Test Fund of Zhejiang Province.
文摘L-carnitine selective polymers were prepared by molecular imprinting using methacrylic acid as the functional monomer. The acid function of the monomer is expected to form hydrogen bond and ionic interactions with the amine function of the target molecule L-carnitine. The imprinted polymers were used as stationary phases in high-performance liquid chromatography (HPLC). It was shown that L-carnitine imprinted polymer exhibited a higher affinity to its template molecule, while the non-imprinted polymer had no affinity to the compounds tested. Racemic carnitine hydrochloride was efficiently resolved on the L-carnitine imprinted polymer, and the separation factor is 1.9.
基金the financial support from the National Natural Science Foundation of China (No. 81173009)Technology Bureau in Shenyang (No. ZCJJ2013402)+2 种基金the financial support from Project for New Century Excellent Talents of Ministry of Education (No.NCET-12-1015)Specific Science Foundation of Shenyang Pharmaceutical University (No. ZCJJ2014409)National Undergraduate Training Program for Innovation and Entrepreneurship (2016)
文摘A simple and rapid UPLC–MS/MS method to simultaneously determine gemcitabine and its L-carnitine ester derivative(2’-deoxy-2’, 2’-difluoro-N-((4-amino-4-oxobutanoyl) oxy)-4-(trimethyl amm-onio) butanoate-cytidine, JDR) in rat plasma was developed and validated.The conventional plasma sample preparation method of nucleoside analogues is solidphase extraction(SPE) which is time-consuming and cost-expensive. In this study, gradient elution with small particles size solid phase was applied to effectively separate gemcitabine and JDR, and protein precipitation pretreatment was adopted to remove plasma protein and extract the analytes with high recovery(>81%). Method validation was performed as per the FDA guidelines, and the standard curves were found to be linear in the range of 5–4000 ng/ml for JDR and 4–4000 ng/ml for gemcitabine, respectively. The lower limit of quantitation(LLOQ)of gemcitabine and JDR was 4 and 5 ng/ml, respectively. The intra-day and inter-day precision and accuracy results were within the acceptable limits. Finally, the developed method was successfully applied to investigate the pharmacokinetic studies of JDR and gemcitabine after oral administration to rats.
基金supported by grants from the Natural Science Foundation of Hubei Province(No.2016CFB352)Hubei Province Health and Family Planning Scientific Research Project(No.WJ2017M011)China Scholarship Council(No.201706275124)
文摘A variety of natural and artificial cryoprotectant extenders have been explored to enhance sperm recovery following cryopreservation-thawing process. The current investigation is aimed at evaluating the effect of acetyl-L-carnitine on human spermatozoa and reactive species oxygen(ROS) level after freezing-thawing process. The spermatozoa were collected from 35 male patients diagnosed as having asthenospermia. The cryopreservation of human spermatozoa treated with acetyl-L-carnitine at different concentrations(group B: 2.5 mmol/L, group C: 7.5 mmol/L, group D: 15 mmol/L) was compared with control(group A: no acetyl-L-carnitine given). For the frozen-thawed spermatozoa, the viability, motility and DNA integrity were measured by comet assay, acrosome integrity by FITC-PNA staining and ROS level was determined in each group. The results showed that there were no significant differences in motility and viability between group A and group B, while the motility and viability of spermatozoa in group C and group D were significantly increased as compared with those in group A. As compared with group A, the values for DNA integrity parameters including comet rate(CR), tail DNA percentage(TD), tail length(TL) and Oliver tail moment(OTM) were significantly reduced in group C and group D. Group C and group D also displayed a higher proportion of intact acrosome than group A. No significant difference in ROS level was found between group A and group B, while with the increase in acetyl-L-carnitine concentration, the ROS level in groups C and D was significantly reduced as compared with that in group A. In conclusion, acetyl-L-carnitine at a concentration of 7.5 mmol/L is an effective antioxidant against cryo-damage on post-thawed human spermatozoa.
基金supported by a grant from Ataturk University Scientific Experimental Project Office to Project Number 2012/07
文摘Several studies have demonstrated that L-carnitine exhibits neuroprotective effects on injured sciatic nerve of rats with diabetes mellitus. It is hypothesized that L-carnitine exhibits neuro-protective effects on injured sciatic nerve of rats. Rat sciatic nerve was crush injured by a forceps and exhibited degenerative changes. After intragastric administration of 50 and 100 mg/kg L-carnitine for 30 days, axon area, myelin sheath area, axon diameter, myelin sheath diameter, and numerical density of the myelinated axons of injured sciatic nerve were similar to normal, and the function of injured sciatic nerve also improved signiifcantly. These ifndings suggest that L-carnitine exhibits neuroprotective effects on sciatic nerve crush injury in rats.
文摘Summary: The effects of L-carnitine, as an ingredient of cardioplegia solution, on cardiac function and cardiomyocyte apoptosis in patients undergoing heart valve replacement operation were investigated. Twenty-three cases undergoing heart valve replacement with cardiopulmonary bypass (CPB) were randomly allocated into two groups: L-carnitine group (n=12, 12 g/L L-carnitine was put in the ST. Thomas cardioplegia) and control group (n=11, identical to the L-carnitine group except that normal saline was administered instead of L-carnitine). Serum cardial troponin I (cTnI) levels, the left ventricular ejection fraction (LVEF), and cardiac index (CI) were measured perioperatively. A bit of myocardial tissue obtained from right atria was taken before CPB and by the end of intracardiac procedure to undergo electron microscopy examination and estimate apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL). From the end of CPB to 3 days after operation, the serum levels of cTnI in the L-carnitine group was significantly lower than that in the control group (P〈0.05). Heart color ultrasonogram showed that the CI index and LVEF at 7th day postoperatively in the L-carnitine group were significantly higher than in the control group (P〈0.05). Compared to the control group, L-carnitine significantly alleviated the morphologic changes of cardiac muscle cells (electron microscopy examination) and decreased the amounts of apoptotic cardiac muscle cells (TUNEL). Furthermore, the dosage of vasoactive drugs used after operation was significantly less in the L-carnitine group (P〈0.01). It was concluded that L-carnitine cardioplegia solution could improve cardiac function in patients undergoing heart valve replacement operation and alleviate CPB-mediated apoptosis of cardiac muscle cells.
文摘BACKGROUND Non-alcoholic fatty liver disease(NAFLD)dominates the landscape of modern hepatology.Affecting 25%of the general population,there is critical unmet need to identify broadly available,safe and cost-effective treatments.Cumulative evidence in animal and human models suggests that intrahepatic and skeletal muscle fatty acid oxidation is impaired in NAFLD,such that lipid accretion is not matched by efficient utilisation.L-carnitine is a crucial mediator of fatty acid metabolism in vivo,promoting mitochondrial lipidβ-oxidation and enhancing tissue metabolic flexibility.These physiological properties have generated research interest in L-carnitine as a potentially effective adjunctive therapy in NAFLD.AIM To systematically review randomised trials reporting effects of dietary L-carnitine supplementation on liver biochemistry,liver fat and insulin sensitivity in NAFLD.METHODS Search strategies,eligibility criteria and analytic methods were specified a priori(PROSPERO reference:CRD42018107063).Ovid MEDLINE,Ovid EMBASE,PubMed,Web of Science and the Cochrane Library were searched from their inception until April 2019.Outcome measures included serum concentrations of alanine and aspartate aminotransferase(ALT and AST),liver fat and insulin sensitivity assessed by the homeostasis model of insulin resistance(HOMA-IR).A random effects meta-analysis was performed for,ALT,AST and HOMA-IR measures separately.Between-study heterogeneity was measured using I2 statistics.RESULTS Five eligible randomised trials were included in the qualitative and quantitative synthesis(n=338).All of the 5 included trials assessed the effect of L-carnitine on serum ALT,identified from Italy,South Korea and Iran.Weighted mean difference(WMD)for ALT between L-carnitine and control groups after intervention was-25.34 IU/L[95%CI:-41.74-(-8.94);P=0.002].WMD for AST between L-carnitine and control groups was-13.68 IU/L(95%CI:-28.26-0.89;P=0.066).In three studies(n=204),HOMA-IR was evaluated.WMD for HOMA-IR between L-carnitine and control groups was-0.74 units[95%CI:-1.02-(-0.46);P<0.001].Two studies using validated outcome measures reported a significant reduction in liver fat in L-carnitine vs control groups post-intervention(P<0.001).CONCLUSION Pooled results indicate that L-carnitine supplementation attenuates ALT,liver fat and insulin resistance in NAFLD cohorts,confirming a beneficial effect of Lcarnitine for a highly prevalent condition with a growing economic burden.
基金Supported by Science and Technology Development Plan of Yantai City(2011074)Shandong Provincial Natural Science Foundation,China(ZR2010HL068)
文摘[ Objective] The paper was to study antioxidant effects of L-carnitine (LC) on rabbit, and explore its impact on SOD, GSH-PX, CAT, T-AOC and MDA activity in the plasma, brain tissue and cerebrospinal fluid of rabbit. [ Method] The healthy matured New Zealand rabbits with big ears were intragastrically administrated with LC at the dose of lmL/kg, and SOD, GSH-PX, CAT, T-AOC and MDA activities in plasma, brain tissue and cerebrospinal fluid of rabbit were determined at different periods before and after administration, respectively. [Result] After LC administration, SOD, GSH-PX CAT, and T-AOC activity in plasma, brain tissue and cerebrospinal fluid increased significantly (P 〈 0.05 ), while MDA content decreased significantly (P 〈 0.05). [Condusion ] LC oral solution shows antioxidant effects on rabbit.
基金Yantai Science and Technology Development Plan( 2011074)
文摘[Objective] To study the effects of L-carnitine (LC) on lowering the high blood lipid and antioxidation in hyperlipidemia rats. [Method] 50 healthy SD rats were randomly divided into 5 groups. They were fed with standard diet, high-cholesterol diet and high-cholesterol diet with 0.25, 0.5, 1.0 g/( kg · d) LC. After the LC groups were consecutively orally administered LC for 28 days, rat serum total cholesterol ( TC), triglyceride (TG), high density lipoprotein ( HDL-C), low density lipoprotein (LDL-C) content, as well as super oxide dismutase (SOD) activity and malondial- dehyde (MDA) content in serum and liver were determined. [ Reset~ Compared with the high-fat model group, LC could significantly reduce the se- rum TC, TG, LDL-C levels, increase HDL-C level, and enhance SOD activity in serum and liver, decrease the content of MDA ( P 〈0.05). [ Con- Clusion] LC might have a significant role in lowering the high blood lipid and improving internal antioxidant capacity in hyperlipidemia rats.
文摘The present study was aimed to observe the effects of urea ingestion, non-protein nitrogen, on the disorder of nitrogen metabolism with the L-carnitine contents using the blood, kidney, liver, and femoral muscle as markers. A total of 8 Japanese white rabbits were used in this experiment. They were fed a basal diet prepared for the control group and the nitrogen volume proportionated to one-third of CP 14%, was replaced with urea in the feed of the experimental group for 7 days. On the final day, the animals were fasted from the previous evening and sacrificed. Blood was collected into a test tube at the same time of the sacrifice and their heart, kidney, liver and femoral muscle were collected. The L-carnitine contents in each sample and the urea in the blood were determined. The results of the growth test showed that there was no significant difference. Furthermore, there was no significant difference in the contents of L-carnitine and urea in each sample. It was concluded that nitrogen replacement of the diet with urea, in the range of 1/3 of dietary protein, had neither effect on the maintenance of body weight nor nitrogen balance, including the de novo synthesis of L-carnitine.
文摘There is constant low level background radiation from the cosmos but in certain situation the body may be subjected to increased acute or chronic exposure from other sources. This occurs in situations such as radiation accidents, medical use and could possibly occur in military/terrorist incident. Dependent on the type, strength of the actual source, degree of exposure and type of radiation different strategies may be employed to reduce damage to the body tissues. A number of pharmacological agents such as peroxisome proliferator-activated receptor (PPAR) gamma agonists, diltiazem, amifostine and palifermin as well as antioxidants and metabolic compounds have been shown to be effective in preventing and also in reducing the long-term damage of the exposure of the living cells to radiation. The major drawback of synthetic (pharmacological) compounds has been that they are highly toxic at the optimum protective dose. Studies have shown that various endogenously found compounds such as L-carnitine, and its derivative acetyl-L-carnitine, are able to protect tissues and organs against various forms of toxic insult including radiation damage. The radiation-induced chronic injury may also be counteracted by other metabolic compounds with amine groups and antioxidant properties similar to the carnitines such as cysteine, 3,3’-diindolylmethane (DIM) and N-acetylcysteine. This review discuses the radioprotective compounds as well as the potential mechanism of cellular protection against radiation by carnitines and other compounds.
文摘Background: Propofol inhibits fatty acid oxidation and induces mitochondrial deficiency, a possible mechanism involved in propofol infusion syndrome. This study investigated how propofol influences fatty acid, glucose, and amino acid metabolism, as well as whether L-carnitine may improve suppression of free fatty acid metabolism. Methods: Male Sprague-Dawley rats, fasted for 16 hours, were allocated to the following two groups: (Group P;continuous intravenous administration of 10 mg/kg/h propofol;n = 8) and (Group P + C;intravenous administration of 50 mg/kg and then 50 mg/kg/h L-carnitine continuously;n = 8). Concentrations of glucose, free fatty acid (FFA), amino acids, in-sulin, and β-hydroxybutyric acid were measured at the start and then one, two, and three hours after propofol administration. Intrahepatic triglyceride levels were measured at the end of experiments. In vitro experiments comprised measurement of oxygen consumption in human hepatocytes (Hepg2) and investigating dependency on palmitic acid, glucose, and glutamine as fuel during propofol administration, with or without L-carnitine. Results: FFA increased in Group P and gradually decreased in Group P + C. There were significant differences between the two groups (Group P;331.2 ± 64.5 μM vs. Group P + C;199 ± 73.6 μM). Glucose decreased in both groups (Group P;53.8 ±16.6 mg/dL vs. Group P + C;88 ± 11.3 mg/dL). Amino acid concentrations were higher in Group P + C after experiments;alanine and glutamine increased significantly. β-hydroxybutyric acid increased significantly in Group P + C, and intrahepatic triglyceride decreased in Group P + C. Dependency on fatty acid metabolism significantly decreased with propofol only;addition of L-carnitine prevented these effects. Conclusions: Propofol impaired mitochondrial fatty acid metabolism, which was compensated mainly by a switch to glucose metabolism and partially by amino acid metabolism. Addition of L-carnitine may improve this imbalance of energy metabolism.
文摘One group of six male control rats [12 months old] and one group of six male rats of the same age, singularly maintained in a cage, and treated with acetyl-L-carnitine-HCl [(gamma-trimethyl-beta-acetyl-butyrobetaine-HCl: Sigma-Tau code ST200 or ALCAR: 60 mg/kg/day[7]/po)] for six months were tested in the spatial learning/memory Morris mazewater task and for atrophy and cell loss in seven myelo- and cytostructurally defined basal forebrain (BF) cholinergic regions [Freddi et al., 2009]. Coronal sections 25 ?m thick were cut through the BF regions and processed every 200 ?m for choline acetyltransferase (ChAT) immunohistochemistry. The ALCAR-treated rats had significantly shorter exit times on the Morris maze-water task test than the control rats (average ± SD 28.3 ± 12.4 s vs. 61.16 ± 4.67 s;t = 6.07, DOF = 10, P = 0.0001). Degenerative morphological changes in the BF ChAT-positive cells were observed in the substantia innominata pars anterior of the control rats but not in the treated animals (P < 0.05). In the BF, the counted and estimated average number of ChAT + cells in the 12-month-old ALCAR-treated rats (ChAT-ALCAR-12+ [Nos. 2,3,4]) was higher but not significantly (15.288 ± 3281) than that counted and estimated in the 12-month-old control rats [(ChAT-CT-12 [Nos. 1,2,3]) (11.508 ± 3868), t = 1.82, DOF = 10, P = 0.319]. In the substantia innominata pars posterior, the ChAT+ cells were significantly more numerous (P < 0.05) in the 12-month-old ALCAR-treated rats (ChAT-ALCAR-12 + [Nos. 2,3,4]) than in the control rats (ChAT-CT-12 [Nos. 1,2,3]). Above all, these results dem-onstrate that treatment with ALCAR from the age of 6 up to 12 months significantly attenuated spatial learning/memory impairment on the Morris maze-water behavioral task (P < 0.001) and also importantly reduced degeneration in size and number of cholinergic cells in the nucleus basalis magnocellularis of the BF. Accordingly, the surviving cholinergic neurons found in the BF of the ALCAR-treated rats might play an important role in modulating cortical activity and facilitating processes of attention, learning and memory.
文摘This study evaluated the relationship between serum L-carnitine level and sperm parameters in young boars. Serum L-carnitine and semen characteristics were determined for 61 young Duroc boars between the ages of 590 and 630 days. Multiple linear regression analysis was performed to predict total and progressive motility and the total number of spermatozoa based on serum total L-carnitine and free L-carnitine levels. Total number of spermatozoa was not associated with basal serum L-carnitine levels. A regression equation was found in which both total L-carnitine levels and free L-carnitine levels were significant predictors of total and progressive motility (P 0.05). These results suggest that serum L-carnitine level is an important selection parameter for stock boars.